Lindl.
Description
Dendrobium hookerianum, Hooker's dendrobium, is an eastern Himalayan epiphytic orchid known from China, India, Bhutan, Myanmar and Nepal, with 127 GBIF occurrences concentrated in the moist mid-montane forests of the region. It grows on tree trunks and branches in humid temperate broadleaved and conifer forest, broadly between about 1500 and 2500 m. The illustrated plants were recorded in Bhutan at Wangdi (Wangdue) at 2500 m in September and at Trashigang at 2000 m in October, autumn-flowering populations in mist-laden forest where cool nights and high humidity prevail.
The species forms long, pendent or arching, slender stems clothed in tubular sheaths and bearing many distichous, lanceolate, thin-textured leaves. From the upper nodes arise lateral racemes carrying several large, golden-yellow flowers. The spreading, elliptic sepals and broader petals are clear yellow, and the broad, suborbicular, fringed labellum is conspicuously marked with two deep maroon to blackish blotches on the disc and edged with a dense marginal fringe. The mentum is short, the column with a prominent foot, and the pollinia waxy.
Named in honour of Sir Joseph Dalton Hooker, the species belongs to Dendrobium section Dendrobium and is prized among Himalayan orchids for its showy fringed lip. Its restricted eastern Himalayan range, autumn flowering and ornamental appeal make it a target for collectors, and combined with ongoing forest clearance this renders wild populations vulnerable. International trade in the genus is regulated under CITES Appendix II.
Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Orchids of Bhutan, Dendrobium and its Relatives (Lavarack et al.)